1. Technical Field
The present invention relates, in general, to a method of loading data, and, more particularly, to a method of loading data about three-dimensional (3-D) images for a navigation system.
2. Related Art
A typical navigation system guides a driver in a suitable traveling direction when an intersection (a fork in the road) appears ahead a vehicle the driver is driving. Here, the driver can be guided by, for example, a visual information display device, an audio information providing device, or both. The display device may display information in an enlarged view.
FIGS. 1A to 1B are diagrams showing examples of enlarged views of an intersection displayed in a conventional navigation system. Referring to FIGS. 1A and 1B , the enlarged views of the intersection are shown by merely magnifying a digital map, as shown in FIG. 1A, outputting a separately prepared road pattern image, as shown in FIG. 1B.
However, such display examples are problematic in that the information about the intersection or other roads is presented in a non-realistic look and in two dimensions.
Accordingly, technology for displaying road information as a 3-D image has been proposed with the development of technology for navigation systems in terms of hardware and software. FIG. 2 is a diagram showing an example of the display of a 3-D image of an intersection. Referring to FIG. 2, 3-D image data is convenient for drivers in that the information presented to the drivers is realistic.
Nonetheless, outputting the 3-D image stably requires processing a large size of data in a short time. That is, in practice, if the data processing speed decreases, the time taken to load required data increases, thus making it difficult to load real-time 3-D image data about geographic features, geographic objects, and roadways (hereinafter referred to as ‘objects’), unless an expensive high-performance hardware is provided.
One method was proposed to solve this problem, in which 3-D image objects are prioritized and loading only objects having a priority above a predetermined priority. However, prioritizing all objects imposes a great burden on the system.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.